Pneumatic hammer.



J. E. BURTLE.

PNEUMATIC HAMMER.

APPLICATION FILED AUG. 26, 190e.

968,236. j Patented Aug. 23.1910.

' a SHEETS-SHEET 1.

Y JOSEPH E. UHTLE.

J. E. BURTLE, PNBUMATIG HAMMER.

APPLICATION FILED AUG. 26, 1908. 968,236, Patented Aug. 23, 1910.

' 3 SHEETS-SHEET 2. m18

JD'SEPH EBQRTLE- I 31d" .1! il Illmlza ni ll I J.E,.BURTLB. i PNBUMATIG HAMMER. AP'rLIaATIoN FILED AUG. 2e. 190g.

' t hanna-sanz; a.A

l JUSEFHEBUR'TAL E,

Patented Aug. 23. 1910- l mers and the UNITED STATES PATENT OFFICE.

JOSEPH E. BURTLE, OF SPRINGFIELD, ILLINOIS.

PNEUMATIC HAMMER.

T o all whom it may concern:

`Be it known thatl I, JOSEPH E. BURTLE, a citizen of the United States, residing at Springfield, in the county of Sangamon and State of Illinois, have invented a new and useful Improvement in Pneumatic Hammers, of which the following is such a full, clear, and exact description as will enable others skilled in the art to which it appertains to make and use my said invention.

This invention relates to pneumatic hampurposes of the invention are to provide in communication with the cylinder of the hammer, a valve controlling the admission of air to the cylinder and the discharge of air from the. cylinder; to provide means for operating said valve; and to provide other new and useful features of construction, shown in the drawings, and here` inafter described and finally recited in the claims.

Referring to the drawings in which similar reference numerals and characters designate like parts in the several views: Figures 1 and 2 are respectively a side elevation and front elevation of the complete machine. Fig. 3 is a transverse section on the zig-zag line X. X. of Fig. 1. Fig. 4 .is an enlarged front elevation of the cylinder and connected parts. Fig. 5 is a vertical longitudinal section on the line Y. Y. of Fig'. 4. Fig. 6 is a horizontal section on the line Z. Z. of Fig. t. Fig. 7 is an enlarged,horizontal section on the line lV. lV. of Fig. 1. Fig. 8 is an enlarged horizontal section on the line V. V. of Fig. 1, and Fig. 9 is an enlarged horizontal section on the line U. U. of Fig'. 1, looking upward.

The main struct-ure is of cast iron and comprises a vertical standard 1; secured on a suitable horizontal base 2. Braces, 3 and 8 are integral with the standard 1. The brace 3, extends through an opening 4, in one wall of the anvil block 4; and the lower end of the brace rests firmly upon the upper surface of the base 2, and gives stability to the standard; and that part of the brace projecting into the anvil block facilitates the placing of the anvil block centrally under the hammer head, and also serves to prevent lateral displacement of the anvil block. Braces 5 integral with the upper part of the standard, lie under and strengthen the box member 6, which is also integral with the standard. A complemental box member 7 is secured on the member 6 by bolts 8. The l Specification of Letters Patent. Application filed August 26, 1908.

Patented Aug. 23, 1910. sei-iai No. 450,400.

shaft 9 turns in the boX formedby the members 6 and 7. A crank disk 10, and a pulley, 11, are secured on the shaft, 9. One end of the connect-ing rod, 12, fits on a wrist pin, 13, on the crank disk 10.

A bracket 14, integral with the standard 1, supports the cylinder 15, and the cylinder is connected with the bracket by bolts 15. Slidable cup-shaped pistons 16, and 17, fit in the bore of the cylinder 15. It is found in practice that the air compressed in the cups of the pistons serves to keep the pistons in alinement and the heat resulting' from the sudden compression of air within the cups serve to cause a degree of expansion of the rims of the cups, suflicient to prevent leakage of air around the pistons, thereby avoiding the necessity for using packing rings on the pistons.

A block 1S, is secured on the piston 16 and a pin 19 connects the rod 12 with the block 18. The hammer-rod 20, is securely connected with the piston 17. The hammer head 21, is detachably connected with the t-he lower end of the rod 20. In the drawings I have shown a dove-tail lug on the hammer head, fitting in a corresponding channel in the lower end of the rod; but any other suitable connection may be used.

An opening 15d extends through the wall of the cylinder l5. A nipple 22 screws into the opening 15El and connects the valve body 23 with the cylinder 15. A gate 2a is slidable within the valve body 23. vA vertical stem 25 is Xed on the gate 24.

Parallel vertical rods 27 are slidable in holes 26a in the guides 26. The lower parts 27b of the rods 27 converge and both are secured on the cam bar 28 by rivets 28a, or equivalent means. A cross bar 29 is secured on the rods 27, and the upper part of the stein 25 is connected with the cross bar. Springs 30 surround the rods 27 between the lower guide, 26, and t-he cross bar 29 and act to support the cross bar 29 and the gate 24 connected therewith, in the raised position shown in Fig'. 5, so that normally the valve is open. When the rods 27 are slid downward, and the springs are compressed, the gate 24- will have moved downward, and t-he valve will be closed, and when the pressure is removed, the springs will act on the bar 29 to raise the gate, and open the valve. Nuts 27a on the rods 27 may be screwed upward or downward on the rods, to limit the vertical movement of the rods.

In practice, it is sometimes desirable to so adjust the parts that the valve may close partially tained by screwing down the nuts 27a so that they will strike against the upper surface of the upper guide 26, and stop the rods 27 before they have moved downward far enough to completely close the valve; the extent of the closing of the valve being determined by the position in which the nuts are set.

An approximately semi-circular bottom plate 31 has a radial channel 31 and is secured on the lower end of the cylinder by bolts 32. A latch 33, having a longitudinal slot 33, and a chisel shaped end 33b is slidable in the channel 31a. A toothed plate 34 is secured on the side of the rod 20 adjacent to the end of the latch 33, and the end of the latch engages with the teeth of the plate to support the rod 20 and the connected arts. A roller 35 is mounted to turn in the slot 33a of the latch 33.

Brackets 36 are secured on the cylinder. A lever 37 osoillates" on a pin 36a extending through the brackets. The lower end ot the lever 37 tits in the slot 33a and is connected with the latch 33 by a pin 372L and the upper end of the lever is connected with the bolt 38 by a pin 33a. The bolt 3S is slidable in a hole 15b in the wall of the cylinder 15. A spring 39 surrounds the bolt 38 and acts against the upper end of the lever 37 to cause the lever to slide the latch, 33 inward and hold the end 33b of the latch in engagement with the teeth of the plate 34.

A pedal 40 is mounted to oscillate on bolts 4l which connect the pedal with the base of the standard. Levers 42 are oscillative on bolts 43 which connect the levers with the standard l and the front ends of the levers are connected with the cam bar 28 by a pin 28a. Rods 44 connect the levers 42 with the pedal 40 in such manner that the depressing of the pedal 40 will cause the levers to slide the cam bar 28 downward, and thereby simultaneously move the gate, 24, and the latch 33 as will now be described.

Near the lower end' of the latch bar 2S is a cam 28h which acts on the wheel 35 to slide the latch 33 outward when the latch bar moves downward. The valve being normally open, it is necessary to close or partially close the valve so that the air within the cylinder may be compressed to render the hammer eective. The force of the blow may be regulated according as the valve is but not completely. This is atclosed or partially open. It the valve is completely closed, the hardest blow will be struck; if it is slightly open, a somewhat lighter blow will be struck, and if it is more open, a still lighter blow will be struck. The operator keeps his Jfoot on the pedal 40 and controls the operation of the valve by pressing on or removing pressure from the pedal, and is thereby enabled to accurately gage the force of the blow according to the nature of the work.

Having fully described my invention, what I claim as new and desire to secure by Letters Patent, is:

l. In a pneumatic hammer, the combination of a cylinder, a primary piston and a secondary piston slidable within said cylinder, a rod connected with said secondary piston, a toothed plate fixed on said rod, a valve-body having an opening communicating with the interior of said cylinder between said primary and secondary pistons, a gate slidable in said valve body to control the opening thereof, guides iixed on said cylinder', rods slidable in bearings on said guides, a cross-bar connecting said rods and connected with the stem of said gate, springs surrounding said rods and acting` to lift said rods to raise said gate, a cam-bar connected with said rods and having a cam, levers connected with said cam-bar, a pedal pivotally connected with the main structure, connecting rods connecting said levers with said pedal, a latch adapted to engage the teeth of said toothed plate, a roller mounted on said latch and adapted to be engaged by the cam of said cam-bar, and a spring acting to normally hold said latch in engagement with the teeth of said toothed plate.

2. In a pneumatic hammer, the combination of a cylinder, pistons slidable within said cylinder, a valve body having an opening communicating with the interior of said cylinder between said pistons, a gate slidable in said valve body, guides secured on said cylinder, rods slidable in said guides and connected to operate said gate, and nuts on said rods adjustable to limit the movement of said gate.

In witness whereof I have hereunto subscribed my name at the city of Springield, Illinois, this 8th day of Aug. 1903.

JOSEPH E. BURTLE.

fitnesses EMMOR E. BUCK, A. R. LIVINGSTON.' 

